This invention relates to a propulsion system for a water wheel, and particularly to a propulsion system which conditions the wheel to utilize gravitational forces to augment rotation.
Water wheels are one of the oldest devices known for producing power. However, heretofore water wheels have been extremely inefficient compared to other means for extracting power from a hydraulic head. Water wheels are generally propelled either by the paddle effect caused by the extremities of the wheel being placed in a moving stream, or by filling buckets mounted on the wheel with water prior to their moving downwardly on one side of the wheel and then emptying them before they start to move upwardly on the other side of the wheel. In either case the buckets or paddles must be lifted as well as dropped thus cancelling out much of the effect gravitational force has on rotation of the wheel. While gravity obviously does play a significant role in the rotation of a bucket powered wheel, the buckets are located at the same radius with respect to the center of the wheel when being lifted as when dropping. Since, for structural reasons, the weight of the buckets themselves must be quite large relative to the water they carry, the amount of power created due to gravity still remains small in light of the massive size of the water wheel.
Rutkove, U.S. Pat. No. 2,850,261 attempts to solve this problem by providing a paddle type water wheel where the paddles include weighted pontoons which are moved to a larger radius when they are on the downward portion of their travel than when they are on the upward portion of their travel. However, he uses the buoyancy force caused by the pontoons entering the stream of water to offset the opposed pontoon to the larger radius.
This has two disadvantages. Firstly, lifting the pontoons due to their buoyancy as they enter the water is somewhat self-defeating since as they initially enter the water the buoyancy force includes a tangential component, which is counter to rotation, as well as a radial component which lifts the pontoon. Thus the lifting of the pontoons is at least partially caused by lost rotational energy of the wheel. Secondly, even though the pontoons in Rutkove are at a larger radius during downward travel than they are during upward travel, their weight remains constant and thus the increased lever arm is not utilized to the maximum effect.
What is needed, therefore, is a water wheel of the type where the pontoons or buckets are at a greater radius when traveling downward than when traveling upward wherein the translation of the pontoons from the smaller radius to the larger radius position results primarily from the energy of the water course by which the wheel is propelled rather than from a loss of rotational energy of the wheel.
The water wheel of the present invention accomplishes the foregoing result by providing a water course which includes a stream of water that flows directly below the water wheel, into which the pontoons are submersed during the bottom portion of their travel, a chute which causes the water to drop substantially vertically before it passes under the water wheel, into which the pontoons extend through a substantial portion of their downward travel, and a turbulence section located at the intersection of the water course and the chute. The turbulence section is arranged so that the trubulence caused by the falling water is directed generally radially inwardly with respect to the water wheel so that it drives the pontoons radially inwardly as they are initially entering the water course, thus augmenting the natural floatation caused by the buoyancy of the pontoons. In order to assist the lifting of the pontoons a track is located in the sidewalls of the water course and followers located on the sides of the pontoons interact with the track so that the pontoons follow the path of the track as they pass through the water course.
In addition, the pontoons have pivotally mounted doors on their radially outwardly facing walls which are movable between open and closed positions by actuators. Timing means associated with the actuators cause the doors to be opened and then closed as each pontoon approaches its uppermost point and then reopened and closed immediately before it enters the water. Accordingly, water introduced into the pontoons when they are opened the first time by means of a nozzle fills the pontoons so that they are heavier when traveling downwardly. Thereafter immediately before the pontoons enter the water course the doors are reopened causing the water to be dumped so that the pontoons are empty to provide maximum buoyancy when passing through the stream and minimum weight when being lifted upwardly.
Accordingly, it is a principal objective of the present invention to provide a water wheel having peripheral pontoon weights which are located at a larger radius when they are traveling downwardly than when they are traveling upwardly.
It is further object of the present invention to provide such a water wheel wherein the pontoons are lifted primarily due to the water which propels the system.
It is a further object of the present invention to provide such a system wherein the pontoons are lifted at least partially due to the turbulence of falling water.
It is a further object of the present invention to provide such a system wherein the pontoons are openable for filling with water prior to their downward travel.
The foregoing objectives, features, and advantages of the present invention will be more readily understood upon consideration of the following detailed description of the invention taken in conjunction with the accompanying drawings.